Siemens SINAMICS G120P Hardware Installation Manual page 42

Connecting
4.3 Motor cable lengths and cross-sections
CAUTION
Cable cross-section for grounding
The material of the protective grounding conductor must be the same as the material of the
power cable. If this is not the case, the specific resistance of the protective grounding
conductor must not be higher than the specific resistance of the power cables. The relevant
diameter of the power cables is the diameter of the line supply cable, and not the diameter
of the motor cable.
For power cables up to 10 mm² (16 mm² Al), as a minimum, the ground cable must have
the cross-section of the power cable.
For power cables larger than 10 mm² (Cu) or 16 mm² (Al) then the ground cable must have
a minimum cross-section of 10 mm² (Cu) or 16 mm² (Al) (larger cross-sections are not
required).
For power cables with a diameter of more than 35 mm
must have at least half of the size of the cross-section of the power cable.
42
the protective grounding conductor
2
Hardware Installation Manual, 11/2014, A5E35319202B AA
PM230 Power Module IP55